Bacterial vaginosis (BV) is the most prevalent form of vaginitis worldwide and has been linked to complications such as preterm birth and STD/HIV acquisition. The etiology of BV remains unknown although its epidemiology mirrors that of a sexually transmitted disease. Most of the microorganisms associated with BV are detected by culture techniques in the healthy vagina in small numbers with the exception of Mobiluncus spp. which seems to be strongly associated with BV. However, this organism is a highly fastidious anaerobe and culture may underestimate the true prevalence in vaginal samples. We propose to use polymerase chain techniques (PCR) to examine the concordance rates of Mobiluncus species among sexual partners. Our hypothesis is that Mobiluncus curtisii is important in the pathogenesis of BV and high concordance rates among sexual partners will be found suggesting sexual transmission.